Pull indicator



Dec. 31, 1935. J. w. WUNSCH ET AL PULL INDICATOR Filed May 22, 1951 I INVENTORS Joseph W Mlnsc'b,

and Har Wunsclt Patented Dec. 31, 1935 I UNITED STATES PATENT OFFICE PULL INDICATOR Joseph W. Wunsch and Harry Wunsch,

Brooklyn, N. Y.

Application May 22, 1931, Serial No. 539,240

1 Claim. (Cl. 265-24) Our invention relates to hoisting mechanism l2 so that as the hoist frame is depressed it will and particularly to means for indicating the pull depress the movable end of the lever l2 in proon the hoist rope or cable. For many purposes portion to the amount of depression of the frame. it is desirable to know the pull upon a hoisting By properly calibrating the indicator scale the 5 cable while it is in use. pull on the cable may be indicated in any de- 6 The main object of our invention, therefore, sired system of measurement such as pounds, is to provide simple but reliable mechanism kilograms, etc. which will indicate to the operators at any time In this connection it should be understood that just what the pull on the cable is. Such a dewe use the term indicator broadly to cover any 10 vice is useful for controlling the safe operation suitable form of device which will enable the 10 of the hoist and also for testing purposes so that operator to determine what the pull has been. it may be applied for continuous use or occa- It is immaterial whether this indication is a sional use as the occasion may require. temporary one by means of a pointer or whether The accompanying drawing illustrates an end the action of the indicator is recorded on a chart View of a hoisting drum embodying the improved or otherwise registered or recorded. 15

indicating mechanism. We also wish it understood that the spring The winding drum 5 may be of any suitable is typical of any suitable type of resilient supcharacter and driven in any suitable manner port or resistance to the movement of the movto wind and unwind the cable 6, the pull of which able member of the system.

it is desired to know. This drum is mounted on Changes in detail may be resorted to with- 20 a u tabl Supp frame which in turn out departing from the principle of the invenis mounted on a platform 8 which is pivoted at tion.

9 to a stationary support. The opposite end of We claim: the platform 8 is supported on a resilient bar A pull indicator comprising a supporting I8 which in turn is supported by knife edges ll. frame, a pivot support for one part of the frame 25 The knife edge II is also preferably interposed and a resilient support for another part of the between the platform and the resilient bar. frame, a driving shaft rotatably supported by It will be seen that the pull on the cable 6 said frame, a winding drum carried on said will tend to depress the supporting frame 1 and shaft, a pulling cable secured to said drum, a

the platform 8, thus displacing a part of the lever associated with said frame and actuated 30 bar I 6 an amount which will be a function of by movement of the frame caused by a tanthe pull. This displacement can be measured in gential component of the torque of said driving anumber of ways. For instance, we have shown shaft, and means connected to said lever for a lever l2 pivoted at l3 and having its movable indicating the pull on said cable.

end connected to a rod l4 and a conventional form of indicator 15. A pin or knife edge l6 JOSEPH w WUNSCE carried by the hoist frame 1 engages the lever H R WUNSCIL 

